Automatically opening tool with sliding scale release

Abstract

An automatically opening tool with a sliding scale release. The assembly includes a modular body; a tool; a gear assembly attached to the tool; a first resilient member for rotating the tool; a sear configured to mate with the gear assembly; a second resilient member for imparting a resilient force to the sear; and cover plates. When the tool is closed, moving the cover plate causes the tool to open automatically.

What is claimed is: 
     
       1. An automatically opening tool, comprising:
 a frame having first and second side portions with a cavity therebetween and a hole with a first diameter through the first side portion; 
 a rotatable shaft on the frame, the shaft having a camming surface and a pair of V-shaped notches on opposite sides of the camming surface; 
 a tool operatively coupled to the shaft and pivotable into and out of the cavity; 
 a bias member resiliently biasing the shaft into rotation; 
 a sear having a V-shaped tip matching the V-shaped notches; 
 a resilient member urging the sear into camming engagement with the shaft; and 
 a frame cover reciprocally mounted on the first side portion of the frame, the frame cover operatively attached to the sear; 
 wherein the shaft has a stepped configuration with a major diameter substantially equal to the first diameter and a minor diameter, smaller than the major diameter, the V-shaped notches are in the major diameter of the shaft and the minor diameter of the shaft extends through a proximal end of the tool, to pivotally couple the tool to the frame. 
 
     
     
       2. The automatically opening tool of  claim 1 , wherein the tool is a knife blade. 
     
     
       3. The automatically opening tool of  claim 1 , consisting essentially of the frame, one or two frame covers, the tool, the shaft, the sear, the bias member, the resilient member and connectors. 
     
     
       4. The automatically opening tool of  claim 1 , wherein the frame, the shaft, the sear, the tool, and the frame cover fit together in a puzzle-fit engagement. 
     
     
       5. The automatically opening tool of  claim 4 , wherein the puzzle-fit engagement requires no more than two fasteners to secure the frame, the shaft, the sear, the tool, and the frame cover into a functioning automatically opening tool. 
     
     
       6. A method of operating a tool, comprising sliding the frame cover of the tool of  claim 1  to disengage the sear tip from one of the V-shaped notches. 
     
     
       7. A method of assembling an automatically opening tool, comprising the steps of:
 providing a frame having two parallel walls with a cavity therebetween and a shaft opening of a first diameter in at least one of the walls at the distal end of the frame; 
 placing the proximal end of a blade, having a pivot hole in its proximal end, in the cavity and aligning the pivot hole with the shaft opening; 
 inserting a shaft having a stepped configuration with a major diameter substantially equal to the first diameter and a minor diameter smaller than the first diameter, the major diameter having a pair of V-shaped notches on opposite sides thereof through the shaft opening and the pivot hole; 
 attaching the tool to the shaft, such that the tool and the shaft rotate together about the shaft opening; 
 engaging the tip of a sear into one of the notches, such that the tip of the tool is in the distal location; 
 covering the sear with a scale and attaching the scale to the sear, such that sliding the scale in the proximal direction, away from the shaft, disengages the tip of the sear from the V-shaped notch; and 
 attaching a resilient member to the shaft, to bias the shaft into rotation, to assemble the tool of  claim 1 . 
 
     
     
       8. The method of  claim 7 , wherein the frame is substantially a mirror image along its longitudinal axis and comprising the step of reassembling the tool as a mirror image, with the scale and the sear on the opposite side of the frame. 
     
     
       9. The method of  claim 7 , wherein the tool is a knife blade and the frame, the shaft, the sear, the tool, and the frame cove are fit together in a puzzle-fit engagement with only two fasteners. 
     
     
       10. The method of  claim 7 , comprising replacing the cover or the knife blade with a different cover or knife blade. 
     
     
       11. An automatically swinging tool, comprising:
 a frame having a first side wall parallel to a second side wall, with a cavity therebetween having a distal end and a top side, the frame having a top side and a bottom side opposite the top side and a distal end opposite a proximal end, the cavity open at least partially at the distal end and the top side of the cavity; 
 an opening having a first diameter in the distal end of the first side wall; 
 a rotatable shaft disposed in the opening and having a stepped configuration with a major diameter substantially equal to the first diameter and a minor diameter, smaller than the major diameter, the shaft having a camming surface and two V-shaped notches on opposite sides of the camming surface in the major diameter portion of the shaft; 
 a bias member resiliently biasing the shaft into rotation; 
 a sear coupled to a resilient member at a surface of the first side wall, the resilient member urging the sear in the distal direction, into camming engagement with the camming surface of the shaft, the sear having a V-shaped tip, sized and shaped to fit the V-shaped notches in the shaft, wherein the shaft cannot rotate if the V-shaped tip is engaged in one of the V-shaped notches; 
 a first cover in reciprocating proximal-distal engagement with the first side wall and coupled to the sear, the first cover, the sear and the resilient member adapted and arranged such that moving the first cover in the proximal direction moves the sear, against the force of the resilient member, in the proximal direction and can free the V-shaped tip from the V-shaped notch, and releasing the first cover permits the resilient member to re-engage the sear against the shaft; 
 a tool having a proximal end pivotally coupled to the distal end of the frame, and the minor diameter portion of the shaft extends through the proximal end of the tool, and pivotally couples the tool to the frame, the tool and shaft adapted and arranged such that rotating the shaft rotates the tool. 
 
     
     
       12. The automatically swinging tool of  claim 11 , comprising a resilient kick member coupled to the shaft to urge the shaft to rotate and thereby pivot the tool. 
     
     
       13. The automatically swinging tool of  claim 12 , comprising a mechanism for automatically moving the tool from a closed to an open position consisting essentially of the shaft coupled to the tool and a resilient kick member, and the sear coupled to the resilient member and the first cover. 
     
     
       14. The automatically swinging tool of  claim 11 , wherein the tool is a knife blade. 
     
     
       15. The automatically swinging tool of  claim 11 , wherein the tool is a screw driver, comb, corkscrew or file. 
     
     
       16. The automatically swinging tool of  claim 11 , comprising a coil spring attached to the shaft and adapted to urge the shaft to rotate and thereby pivot the tool. 
     
     
       17. The automatically swinging tool of  claim 11 , wherein the opening is a thru hole through the first and second walls of the frame, which are substantially mirror images of each other. 
     
     
       18. The automatically swinging tool of  claim 17 , wherein the sear is on the outside of the first wall of the frame, between the frame and the first cover, and the frame and sear are adapted to also be reconfigured into a second arrangement, with the sear on the outside of the second wall, in camming engagement with the shaft and the cover in reciprocating proximal-distal engagement with the second wall, over the sear, with the sear coupled to the inside of the first cover over the second wall, wherein moving the cover in the proximal direction disengages the sear from the shaft. 
     
     
       19. The automatically swinging tool of  claim 18 , wherein the tool is a knife and the coil spring is adapted to cause the knife to pivot out from the cavity when the cover is slid to disengage the sear from one of the V-shaped notches on the shaft and the sear re-engages in the other notch in the shaft to lock the knife in an open position.